Guides for assisting in the drilling of holes in materials such as wood, metals and plastics are well known in the art and exemplary of such drill guides are those set forth in the Jenkins U.S. Pat. No. 2,622,458, Dec. 23, 1952; Daniels U.S. Pat. No.2,831,376, Apr. 22, 1958; Converse U.S. Pat. No. 3,827,822, Aug. 6, 1974; Russell U.S. Pat. No. 3,874,810, Apr. 1, 1975; Haddon U.S. Pat. No. 4,729,698, Mar. 8, 1988 and Krogh U.S. Pat. No. 4,765,786, Aug. 23, 1988.
Many of the prior art devices such as Daniels, Converse, Haddon and Krogh require specially designed drills or require a suitable clamp or fastening means in association with the drill to secure the drill for movement with the guide.
Jenkins, on the other hand, discloses a guide device which accepts the chuck in a specially constructed journal supported conical holder through which a drill in the drill chuck of the drill extends. The guide is not effective in practice to maintain the angle of the drill perfectly straight if the operator does not hold the drill straight.
Russell, discloses a two column drill guide wherein the chuck of the drill must be removed from the drill and relocated on the drill guide and the drill itself fastened in such manner that the drill and guide are not thereafter easily separated.
Russell, Haddon, Krogh and Lavering et al, (U.S. Pat. No. 3,381,551, May 7, 1968) disclose as part of their devices or separately (Lavering et al) means for locating the drill guide on the edge of material when drilling holes in the edge of the material. However, these centering or locating systems are not easily and simply adapted for drilling holes in the edges of sheet material or the like.
Accordingly, there is a need for a simple drill guide that may be used with a portable hand drill without having to fasten the drill to the guide or use a specially designed drill and for a drill guide which will also provide for centering the drilling of holes on edges of material without significant adjustment. Further there is a desire to provide a simple depth gauge and handle for use with the drill guide.